Supplemental Balance Sheet, Income Statement and Cash Flow Information (Details 2) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Investment income (loss)
Interest and dividend income	$ 34	$ 2,323	$ 1,636	$ 5,318
Gains (losses) on investments, net	(56)	(134)	492	4,917
Investment income (loss)	$ (22)	2,189	$ 2,128	10,235
Realized gains from the sale of available-for-sale securities		$ 5,000		$ 5,000

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period as a result of selling or holding marketable securities categorized as trading, available-for-sale, or held-to-maturity, including the unrealized holding gain (loss) of held-to-maturity securities transferred to the trading security category and the cumulative unrealized gain (loss) which was included in other comprehensive income (a separate component of shareholders' equity) for available-for-sale securities transferred to trading securities during the period. Additionally, this item would include any gains (losses) realized during the period from the sale of investments accounted for under the cost method of accounting and losses recognized for other than temporary impairments (OTTI) of the subject investments.

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Amount of operating dividend and interest income, including amortization and accretion of premiums and discounts, on securities.

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Amount after accretion (amortization) of discount (premium), and investment expense, of interest income and dividend income on nonoperating securities.

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